JPS6327833A - Method for forming image having heat-resistance - Google Patents

Abstract

PURPOSE:To obtain the excellent image with good efficiency by using a photoresist dry film comprising a photosensitive aromatic precursor capable of converting to the aromatic polymer by a heat-treatment which has the heat- resisting property of >=310 deg.C initial temp. of reducing weight by heating, and a photopolymerization initiator as an essential component. CONSTITUTION:The photoresist film comprises the photosensitive aromatic precursor capable of converting to the heat-resisting aromatic polymer by a heat-treatment, which has >=310 deg.C initial temp. of reducing weight by heating or a soluble photosensitive aromatic polymer having >=310 deg.C initial temp. of reducing weight by heating, and the photopolymerization initiator as the essential component. The image having the heat-resisting property is formed by laminating the photoresist film on a substrate, followed by radiating the photoresist layer through a photomask with an active ray and subsequently, giving a high insulating property to the obtd. layer after developing it. Thus, a spin-coating step can be omitted, and a producing step can be made to automatize.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a method for forming images having heat resistance, and in particular to insulating films for semiconductor devices, alignment films for liquid crystal display devices, and thin film magnetic films that require heat resistance. The present invention relates to a method for efficiently forming excellent images in applications such as insulating films for heads and insulating films for multilayer printed circuit boards.

[Conventional technology]

Conventionally, a method has been used in which a polyimide face is coated as an insulating layer for high-density wiring, etc., and a heat-resistant image is formed by wet etching using a photoresist.

[Problem that the invention seeks to solve]

In this case, there is a drawback that the diameter of the pie hole depends on the thickness of the insulating layer, making high-density packaging difficult.

In order to solve this drawback, attempts have been made to use photoresist as it is as an insulating layer.
It is disclosed in Japanese Patent No. 19695. However, since the heat resistance of the disclosed resin is low, it cannot withstand the heat applied when mounting an LSI, for example, and has the disadvantage of lacking reliability.

Also, Japanese Patent Application Publication No. 59-242494, Japanese Patent Application No. 59-248
In No. 940, the present inventors applied a film such as a photosensitive polyimide precursor onto a base material using a spin coater, a roll coater, etc., dried it, and performed exposure, development, and heat treatment. We proposed a technology to directly form a heat-resistant insulating layer such as polyimide without using photoresist. In the case of this FE coating method, the thicker the insulating layer required, the longer the drying time for the FE solvent, and other process disadvantages, as well as the long exposure to high temperatures during blivata, which leads to problems with the sensitizer. There is a risk of causing a problem that lowers the light anger level. Furthermore, in the case of a thick film, the base material must be kept horizontal, and if it is not kept horizontal, there is a problem that the film thickness becomes uneven.

[Means for solving problems]

In view of the above circumstances, the present inventors have conducted extensive research to provide a method for forming an image with sufficient processability and excellent heat resistance, and as a result, have completed the present invention.

That is, the present invention provides (a) a photosensitive aromatic precursor that can be converted into a heat-resistant aromatic polymer having a thermogravimetric decrease onset temperature of 310° C. or higher by heat treatment, or
A photoresist film containing a photosensitive aromatic polymer soluble at 0° C. or higher and (b) a photopolymerization initiator as essential components is laminated onto a substrate, and the photoresist film is applied through a photomask. The present invention relates to a method for forming an image having heat resistance, which includes a step of irradiating a layer with actinic rays and, after development, making it highly insulative by heat treatment.

The thermal weight loss start temperature of the polymer used in the present invention is a measure of the heat resistance of the polymer, and is the temperature at which the weight loss starts when the polymer is heated from room temperature using a thermobalance or the like by a heating method. Measure. If the temperature at which thermal weight loss begins is less than 310°C, the polymer will partially decompose in the hot atmosphere during processes such as vapor deposition, causing gas generation and blistering.
Usage is restricted.

The polymer used for the photoresist film has a thermal weight loss initiation temperature of 310° C. or higher, preferably 350° C. or higher, and typical examples thereof include polyimide or its precursor.

The photosensitive aromatic precursor used as component (a) of the film used in the present invention, which can be converted into a heat-resistant aromatic polymer having a thermal weight loss onset temperature of 310°C or higher by heat treatment, is as follows:
For example, it is a polymer having a repeating unit represented by the general formula CI).

[In the formula, X is a (2+n)-valent carbocyclic group or heterocyclic group; ,-C
A group that can react with the carbonyl group of OOR to form a ring, n
is 1 or 2, m is Oll or 2, and C0OR
and Z are in an ortho or peri position relationship with each other. ] As X in general formula (1), for example, benzene,
Examples include naphthalene, anthracene, pyridine or thiophene and groups represented by (I,);
Groups represented by 2) to (I4) are preferred.

ΣXa <Σ (I1) -o-, -oQsQo- or a is O or l, X is CH3 or CF3] (r
z) (1B) (I, )) Also, as Y in the general formula CI), for example, (I5) to (
II. ) are mentioned.

[Ya in the formula is H, (:H3-1(CH2)2CH,0
CH5, C0OH.

Halogen atom or 5o3H, Yb is CH, - (where b is O or 1), Yc and Yd are H, CH5, C, H,, OCH3, halogen atom, C00H, 503H or NOl, Ye
and Yf is H, CN.

Halogen atom, CH3, OCH3,5o3)1 or OH
] Specific examples of these Y include the following groups.

Further, as R in the general formula (1), for example, the formula (R
Examples include groups represented by a) to (Rg).

[In the formula, Ro represents a hydrogen atom or a methyl group, R# represents an alkylene group having 1 to 3 carbon atoms, and C represents 1 or 2.

] As an example of (Ra), as an example of (Rb), as an example of (Rc), as an example of (Rd), as an example of (Re), -CHz-CH-Ch, - CH2-CH2-CH=
As an example of CHHz (Rf), as an example of (Rg), etc. Among these, the ester bond type (Ra) to (Rf
) is preferred, and (Ra) is preferred from the viewpoint of photosensitivity.

W in the general formula (I) can be converted to -COO by heat treatment.
A group capable of forming a ring by reacting with the carbonyl group of R, and -C-NH1 is particularly suitable as such a group. Moreover, as n, 2 is preferable.

In addition, the polymer used as component (a) has the general formula (
In I), X-R within the same bonding format Z,
It can also be obtained by copolymerizing one or more types selected from among the combinations of Y-. Alternatively, two or more types of homopolymers or copolymers can be selected and used as a mixture. Further, regarding the synthesis method of a polymer having a repeating unit represented by the general formula (1), for example, Japanese Patent Application No. 60-9918 and Japanese Patent Application No. 60-26739
It is described in the specification of No. 5.

In addition, the thermogravimetric decrease starting temperature used as component (a) is 31
Photosensitive polyimide that is soluble in organic solvents at temperatures above 0°C is
For example, it is a polyimide having a repeating unit represented by the general formula (Ir).

(Left below) [However, in the formula, χ1%XJL, Xl, , Zl, and Z2 are groups having a reactive carbon-carbon double bond, NSp are both non-zero integers from 0 to 2o, and x and y are integers from 0 to 2o. ] General formula (n)
Examples of X5 include aromatic hydrocarbon groups having 6 to 2 carbon atoms, thiophene, pyridine, and formula (Xd)
Examples include groups represented by (Xd-1) and (χd-2
) is preferred.

(, :,, 1mte d is 0 or 1, x゛ is -0-, -C-
, -CH2-1 or X in general formula (I[), -X4
Examples of the group include an aromatic hydrocarbon group having 6 to 20 carbon atoms, thiophene, pyridine, and a group represented by the formula (Xe), with (Xe-1) being preferred from the viewpoint of photosensitivity.

O.C.F.

Examples of Y and -Y3 in the general formula (n) include groups represented by the formulas Yg and Yh, and among these, the group represented by Yk is preferred from the viewpoint of photosensitivity.

R゛2 [However, R2 and R4 each represent an alkyl group having 1 to 6 carbon atoms, and R3 and R3 each represent a hydrogen atom or a carbon number 1
~6 alkyl group is shown. ] -O-, -S-, R4 and P each have 1 carbon number
-6 alkyl group, R, and R1 each represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. ] [However, R
6 and R8 each represent -CH,, -CI(, cH3, or -CH(C)+3)2, and Rwa and R9 each represent -H, -C13, -CH2Cl2, or -C)I(C1
b) Show z. ](Yg), As a specific example of (Yh), Among Zl and Z2 in general formula (n), as a group having a reactive carbon-carbon double bond, for example, the formula ( Za
) to (Zf).

Among these in R1, from the viewpoint of photosensitivity, a group represented by Zg=Zi is preferable.

Further, among Zl and Z2 in the general formula [If], the group having no reactive carbon-carbon double bond is preferably an aromatic hydrocarbon group having 6 to 30 carbon atoms, and specific examples include Zj =Zm is mentioned.

By using a photosensitive precursor that can be converted into a heat-resistant polymer having a glass transition temperature of 350°C or lower and a thermal weight loss onset temperature of 310°C or higher by heat treatment, the bonding with the base material during lamination can be improved. The heat treatment in the present invention means a step of dehydrating and ring-closing the precursor to convert it into a heat-resistant skeleton such as polyimide. Temperature range: 30~
Examples include 180 minutes. Moreover, the glass transition temperature was determined from the linear expansion coefficient. That is, the linear expansion coefficient of the film is TMA
It was measured in the tensile mode of , and was determined from the inflection point. Examples of these precursors include, among polymers having repeating units represented by the above formula (1), those whose polyimide structure obtained by heat treatment has a glass transition temperature of 350'C or less. It will be done. These are, for example, photosensitive polyimide precursors having repeating units represented by formulas (I[a) to (Inc).

BP (Ub) [8175 mol%, 2525 mol% copolymer] "Here, S is 0 or 1, R and X are the above R in formula (II)
has the same meaning as and
~R- are respectively -CH3, -CI (2C13, -C)
(C)13). ](IIa
) Preferred examples of (nb) include B P and Hl (nc ), and as the polymer of component (a), soluble photosensitive polyimide or, When using a photosensitive precursor that can be converted into a heat-resistant polymer with a glass transition temperature of 350°C or higher by heat treatment, the photosensitive precursor can be converted into a heat-resistant polymer with a glass transition temperature of 350°C or lower by these heat treatments. Use of a two-layer dry film containing a precursor as an adhesive layer can provide good adhesion to the substrate.

The photopolymerization initiator used in the present invention is a well-known one, such as benzophenone, methyl 0-benzoylbenzoate, 4,4°-bis(dimethylamino)benzophenone,
4.4'-bis(diethylamine)benzophenone)
, 4.4'-dichlorobenzophenone, 4-benzoyl-4'-methyldiphenone, dibenzyl ketone,
Benzophenone derivatives such as fluorenone; acetophenone derivatives such as 2.2'-jethoxyacetophenone, 2-hydroxy-2-methylpropiophenone, pt-butyldichloroacetophenone; 1-hydroxycyclohexylphenyl ketone, thioxanthone, 2- Thioxanthone derivatives such as methylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, and diethylthioxanthone; benzyl derivatives such as benzyl, benzyl dimethyl ketal, and benzyl-β-methoxyethyl acetal; benzoin derivatives such as benzoin, benzoin methyl ether, and benzoin butyl ether ; anthraquinone derivatives such as anthraquinone, 2-t-butylanthraquinone, 2-amylanthraquinone, β-chloroanthraquinone; anthrone, benzanthrone,
Anthrone derivatives such as dibenzosuberone and methylene anthrone: naphthalenesulfonyl chloride, quinolinesulfonyl chloride, N-phenylthioacridone, 4,4
- Photoreducible dyes such as azobisisobutyronitrile, diphenyl disulfide, penzthiazole disulfide, triphenylphosphine, camphorquinone, carbon tetrachloride, tribromophenyl sulfone, benzoyl peroxide and eosin, methylene blue, and 7-scorbin. A combination of acids, reducing agents such as triethanolamine, 2,6-di(4°-
diazidobenzal)-4-methylcyclohexanone, 2
, 6-di(4'-diazidobenzal)cyclohexanone and other azides, 1-phenyl-1,2-butanedione-
2-(o-methoxycarbonyl)oxime, 1-phenyl-propanedione-2-(0-ethoxycarbonyl)
Oxime, 1-phenyl-propanedione-2-(0-
oximes such as benzoyl) oxime, 1,2-diphenyl-ethanedione-1-(0-benzoyl) oxime, 1,3-diphenyl-propanetrione-2-(0-ethoxycarbonyl) oxime, and Michler's ketone,
Examples include bisalkylaminobenzophenones such as 4,4゛-bis-(diethylamino)-benzophenone;
From the viewpoint of photosensitivity, a combination of oximes and bisalkylaminobenzophenones is preferred.

Further, a compound having a reactive carbon-carbon double bond can also be used in the film composition used in the present invention.

Examples of these compounds include, for example, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, N-vinyl-2-pyrrolidone, carpitol acrylate, tetrahydrofurfuryl acrylate, isobornyl acrylate, 1,6-hexane. Diol diacrylate, neopentyl glycol diacrylate, ethylene glycol diacrylate, polyethylene glycol diacrylate, pentaerythritol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol hexaacrylate, tetramethylolmethanetetraacrylate, tetra Examples include ethylene glycol diacrylate, nonaethylene glycol diacrylate, methylene bisacrylamide, N-methylol acrylamide, and those obtained by changing the above acrylate or acrylamide to methacrylate or methacrylamide.

Among these, polyacrylates having two or more acrylate groups are preferred, and compounds represented by the structural formula M are particularly preferred from the viewpoint of photosensitivity.

(p-1 to 20) Moreover, a sensitizer can also be added to the film composition used in the present invention. This sensitizer can improve the sensitivity of the film, for example, Michler's ketone,
4.4”-bis(diethylamino)benzophenone, 2
, 5-bis(4′-diethylaminobenzal)cyclopentanone, 2.6-bis(4′-diethylaminobenzal)cyclohexanone, 2.6-bis(4″-dimethylaminobenzal)-4-methylcyclohexanone ,2,
6-bis(4°-diethylaminobenzal)-4-methylcyclohexanone, 4,4°-bis(dimethylamino)chalcone, 4,4'-bis(diethylamino)chalcone, p-dimethylaminocinnamylideneindanone, p-
Dimethylaminobenzylidene indanone, 2-(p-dimethylaminophenylvinylene)benzothiazole, 2
- <p-dimethylaminophenyl vinylene) isonaphthothiazole, 1,3-bis(4°-dimethylaminobenzal)acetone, 1,3-bis(4'-diethylaminobenzal)acetone, 3,3'-carbonyl −Bis(
7-dinithylaminocoumarin), jetanolaniline, tolyldetanolamine, triethylamine, isoamyl dimethylaminobenzoate, isoamyl diethylaminobenzoate, etc., but are not limited thereto.

Furthermore, by adding a mercaptan compound to the composition of the film used in the present invention, the photosensitivity can be further improved. Examples of mercaptan compounds include, for example, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 1-phenyl-5-mercapto IH
-tetrazole, 2-mercaptothiazoline, 2-mercapto-4-phenylthiazole, 2-amino-5-mercapto-1,3,4-thiadiazole, 2-mercaptoimidazole, 2-mercapto-5-methyl-1,3
, 4-thiadiazole, 5-mercapto-1-methyl-
IH-tetrazole, 2,4.6-drimerkabuto s
-) riazine, 2-dibutylamino-4,6-dimercapto-s-triazine, 2,5-dimercapto-1,3
, 4-thiadiazole, 5-mercapto-1,3,4-
Thiadiazole, 1-ethyl-5-mercapto-1,2
, 3,4-tetrazole, 2-mercapto-6-nitrothiazole, 2-mercaptobenzoxazole, 4-
Examples include phenyl-2-mercaptothiazole, mercaptopyridine, 2-mercaptoquinoline, 1-methyl-2-mercaptoimidazole, and 2-mercapto-β-naphthothiazole.

Furthermore, a functional dialkoxysilane compound may be added to the film composition used in the present invention, or may be pre-coated on the base material, if necessary. This dialkoxysilane compound is a compound that improves the adhesion of the interface between the heat-resistant polymer film of the composition of the present invention and the base material Si and inorganic insulating film, and examples thereof include: For example, γ-aminopropylmethyldimethoxysilane, N-
(β-aminoethyl)γ-aminopropylmethyldimethoxysilane, T-glycidoxypropylmethyldimethoxysilane, T-mercaptopropylmethyldimethoxysilane, 3-methacryloxypropyldimethoxymethylsilane, 3-methacryloxypropyltrimethoxysilane, dimethoxymethyl-3-piperidinopropylsilane,
jetoxy-3-glycidoxypropylmethylsilane,
Examples include N-(3-jethoxymethylsilylprobyl)succinimide. For information on how to use and effects of these dialkoxysilane compounds, see Japanese Patent Application No. 1983.
It is described in detail in the specification of No.-38242.

-Also, in order to improve the storage stability of the solution of the composition of the film of the present invention, a polymerization inhibitor may be added.

Examples of the polymerization inhibitor include hydroquinone, N
-nitrosodiphenylamine, p-tert-butylcatechol, phenothiazine, N-phenylnaphthylamine, ethylenediaminetetraacetic acid, 1,2-cyclohexanediaminetetraacetic acid, glycol etherdiaminetetraacetic acid,
Examples include 2.6-tert-butyl-p-methylphenol.

In the film composition used in the present invention, the content ratio of the polymerization initiator and sensitizer is preferably 0.1 to 20 M% with respect to the polymer of component (a) or component (b),
More preferably 5 to 15% by weight.

The content of the compound having a reactive carbon-carbon double bond is preferably 20% by weight or less based on the polymer of component (a) or component (b). When the functional dialkoxysilane compound is added and used, its content is as follows:
(b) 0.05 to 10% by weight based on the precursor of the component;
Preferably it is 0.1 to 4% by weight. Further, the content of the polymerization inhibitor is 5% by weight or less, preferably 0.5% by weight or less, based on the polymer of component (a) or component (b).

The film used in the present invention can be obtained by dissolving the composition in a solvent in which all of its components can be dissolved, coating it on a predetermined support using a bar coater or blade coater, and drying it. It can be used with a support or a removable protective film, or it can be used alone by peeling off from the support film.

The solvent is preferably a polar solvent whose boiling point is not too high; for example, N-methylpyrrolidonecyclopentanone, cyclohexanone, etc., and mixed solvents thereof can be used.

The support is preferably transparent, has sufficient strength, and is insoluble in the solvent used, and films such as polyethylene terephthalate and polypropylene can be used. It is preferable to use the same type of film as the protective film. The drying conditions for the applied film are 40 to 10
10-120 minutes in a circulating oven at 0°C. Also, the second
When forming a layer, it is coated on the first layer in a similar manner. The thickness of the 1st r4 is 10-100 μm, the 21st ii
The thickness of i is preferably 3 to 20 μm.

The film thus formed is laminated on a substrate by heating and pressure, with or without the cover film being peeled off, together with the support film.

As this substrate, a silicon wafer, a ceramic substrate, a metal plate made of copper, aluminum, etc., a ceramic substrate having a metal wiring layer, etc. can be used. Furthermore, by pre-blending the functional dialkoxysilane compound or adhesive layer onto this base material, better adhesion between the base material and the film can be obtained. As this adhesive layer, a composition consisting of the above-mentioned photosensitive aromatic precursor, a soluble photosensitive aromatic polymer, a photopolymerization initiator, etc. is preferable, especially in the case of a film or a two-layer film used in the present invention. , the composition is preferably the same as that of the second layer.

These adhesive layer compositions are dissolved in a suitable solvent among the above and applied to a substrate using a spin coater, bar coater, blade coater, screen printing method, or the like. or,
Preferred conditions for laminating the dry film are a roll temperature of 40 to 150°C and a roll pressure of 0.5 to 5 Kg/caT using a Hontrol laminator, particularly preferably 80 to 120°C and 2 to 4 Kg/an! It is.

Further, a method of using a vacuum laminating roll having a chamber capable of evacuating the laminating section is a preferable method in order to prevent contamination of micro air.

The conductive circuit board laminated with the photoresist film is heated, if necessary, to dry the remaining solvent and relieve the tension during lamination.

The support film constituting the photoresist film is peeled off before or after exposure and before development.

If the remaining solvent is to be dried, the support film must be peeled off before exposure. Further, in the case of a support film that dissolves in a developer, there is no need to peel it off.

Exposure is done through a conventional photomask.

Examples of the active light used in this case include ultraviolet rays, X-rays, and electron beams, and among these, ultraviolet rays are preferred, and examples of the light source include, for example, low-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, halogen lamps, Examples include germicidal lamps. Among these light sources, ultra-high pressure mercury lamps are preferred. Further, it is preferable that the exposure is performed in a vacuum or under a nitrogen atmosphere. Further, if necessary, it is also possible to perform heat treatment in the range of 35 to 120° C. after exposure.

After exposure and heat treatment in this manner, development is performed using a dipping method, a spray method, or the like in order to remove unirradiated areas. The developer used in this case is preferably one that can completely dissolve and remove the unexposed film within an appropriate time, such as γ-butyllactone, α-acetyl-T-butyrolactone, N-methylpyrrolidone, N- Even when aprotic polar solvents such as acetyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide, hexamethylphosphoric triamide, and N-benzyl-2-pyrrolidone are used alone, Alternatively, as a second component in these, for example, water or alcohols such as methanol, ethanol, and isopropanol, aromatic hydrocarbon compounds such as toluene and xylene, ketones such as methyl ethyl ketone and methyl isobutyl ketone, ethyl acetate, and propion. A mixture of solvents such as esters such as acid methyl, ethers such as tetrahydrofuran and dioxane may be used.

Furthermore, it is preferable to rinse with a solvent such as the one shown as the second component immediately after development.

By heating in the temperature range of 250 to 500°C, the image thus obtained is heat-resistant with a thermogravimetric loss starting temperature of 310°C, which contains imide rings, isoindoroquinazolinedione rings, oxazinedione rings, quinazolinedione rings, etc. It is converted into a polymeric compound with high insulation properties, and an insulating layer and the like having high insulation properties are formed.

〔Effect of the invention〕

The method of forming heat-resistant images of the present invention has many advantages over conventional methods. The advantage of this is that it uses a dry film, which makes it possible to omit the spin coating process that was conventionally used in writing with this type of material. In other words, sufficient film thickness uniformity, which is limited by spin cords, can be obtained, and throughput is improved by performing all steps from substrate pretreatment to lamination, exposure, development, drying, and heat treatment in a continuous operation. can be obtained, and automation of the manufacturing process is also possible. Furthermore, image formation on a thick insulating layer is facilitated, and each layer can be made into a flat structure.

If the heat-resistant image forming method of the present invention is applied to glabella insulating films and surface protective films for semiconductor devices, and multilayer wiring boards typified by copper polyimide boards, etc., the process will be shortened by reflecting the above-mentioned characteristics. It exhibits features such as being clean and automated, making microfabrication easier.

〔Example〕

Next, the present invention will be explained in more detail with reference to examples, but the present invention is not limited to these examples in any way.

Reference Example 1 32.2 g of benzophenone tetracarboxylic anhydride, 27.0 g of 2-hydroxyethyl methacrylate, and 100a+1 of γ-butyrolactone were placed in a 500 ml separable flask, and 17.0 g of pyridine was added while stirring under water cooling. . After stirring at room temperature for 16 hours,
A solution of 41.28 ml of dicyclohexylcarbodiimide in 40 ml of T-butyrolactone was added over 10 minutes under water cooling.
Then 4,4′-diaminodiphenyl ether 16.0
g was added over 15 minutes. After stirring at room temperature for 3 hours, 5 ml of ethanol was added and stirred for an additional hour. After filtering the precipitate, the obtained solution was added to ethanol in step 11, and the precipitate formed was washed with ethanol and then dried under vacuum. A polymer powder was obtained. This polymer is designated as P-1. The logarithmic viscosity of P-1 was 0.15. 10 g of P-1 was dissolved in 13 g of N-methylpyrrolidone (NMP'), spin-coded onto aluminum foil, and dried to obtain a coating film with a thickness of about 30 μm. This was heat-treated at 400° C. for 1 hour to convert it into polyimide, and the aluminum foil was dissolved with IN hydrochloric acid to obtain a polyimide film. This polyimide film (3I! 5 mm) with a thickness of about 15 μm was subjected to a tensile mode using TMA (TM3000 manufactured by LVAC Shinku Riko Co., Ltd.) under a load of 10 g at a heating rate of 5° C./min, and the coefficient of linear expansion was measured. The glass transition temperature was determined from the inflection point of this coefficient of linear expansion and was 325°C.
Met. In addition, using the same polyimide as above, the thermogravimetric loss onset temperature was measured using a differential thermometer (TGA, Seiko Electronics Industries ■) at a heating rate of 10°C/min.
The temperature was 40°C.

Reference Example 2 To a 43.6 ml DMF solution of 85 g of 3.3°, 4.4'-benzophenone tetracarboxylic dianhydride 4,
4,4"-methylene 2.6 without stirring at 25°C
- A solution of 9.3 g of dinitylaniline in 57.6 ml of DMF was added and stirred at 25°C for 1 hour. Next, 0.55 g of maleic anhydride, 0.63 g of itaconic anhydride and 1 ml of pyridine were added, and the mixture was heated at 25°C. - Stirred for 1 hour.

Next, 6.06 g of 3.3',4,4°-benzophenonetetracarboxylic dianhydride and 1+wl of pyridine were added, and the mixture was stirred at 25°C for 1 hour. Next, 3.3°, 4.4'
1.08 g of -tetraaminobiphenyl ether and 1 ml of pyridine were added, stirred at 25°C for 4 hours, and left to stand for 16 hours. 14. Acetic anhydride was added to the obtained polyamic acid solution.
2 ml and 9.7 ml of pyridine were added and stirred at 40° C. for 3 hours to perform an imidization reaction. Stirring the reaction solution 3
I! After dropping the polymer into water to precipitate it and filtering it out,
It was washed three times with 31 water and vacuum dried. This polymer is designated as P-2. The thermogravimetric decrease starting temperature of P-2 is 430℃
and the logarithmic viscosity was 0.3 (1 g in NMP
/dL measured at 23°C).

Reference Examples 3 to 6 Using the raw materials in Table 1 in the same manner as Reference Example 1, P-3 to P
-6 was synthesized. Table 1 shows the logarithmic viscosity of these polymers, the glass transition temperature after conversion to an imide structure, and the temperature at which thermal weight loss begins, which were measured in the same manner.

Note: 'I' BTDA: Penzophenone tetracarboxylic dianhydride PMD^: Pyromellitic anhydride '4' *NMP: 1% solution Measured at 30°C Example 1 100 g of P-1 as a polymer, 7 molar Trimethylolpropane triacrylate as 1081 as initiator benzyl 4g, as sensitizer Michler's ketone 4g
g SN-phenylethanolamine 2g and 2-mercaptobenzothiazole 2g cyclopentanone 150g
g to obtain solution C-1.

Solution C-1 was coated onto a 25 μm thick polyethylene terephthalate CPET film, and
It was dried for 60 minutes in a circulating oven at .degree. C. to obtain a 40 .mu.m thick film. This film was coated at 110°C using a Hontrol laminator at 2Kg/cIl! It was laminated on a ceramic substrate that had been degreased and cleaned under the following conditions. Peel off the PET film on the laminated film,
Using an ultra-high pressure mercury lamp (8 mW/crA), exposure was performed for 3 min under a nitrogen atmosphere through the mask film. When this was developed with a developer of N-methylpyrrolidone/xylene (1:1 volume) and rinsed with isopropyl alcohol, a sharp pattern was obtained. Heat treatment was performed for 2 hours and at 400° C. for 1 hour to imidize and obtain a polyimide pattern having sufficient adhesion to the substrate.

Example 2.3 Polyimide having sufficient adhesion to the substrate was prepared in the same manner as in Example 1 except that P-4 and P-5 were used instead of P-1 as the polymer of the second RFI composition. I got the pattern.

Example 4 Solution C-2 was prepared using 100 g of P-2 as a polymer, 15 g of nonaethylene glycol diacrylate as a polymer, and the same initiator, sensitizer, and solvent as in Example 1.
I got it. Solution C-2 was coated onto a 25 μm PUT film and dried to obtain a 10 μm thick first layer film. Solution C-1 of Example 1 was coated on top of this, dried, and a second layer was laminated to a thickness of 5 μm. This two-layer film was laminated from the second layer side, and a polyimide pattern having sufficient adhesion to the substrate was obtained in the same manner as in Example 1, except that the exposure time was 5 minutes.

Example 5.6 P-3 and P-6 were used instead of P-2 as polymers, and the first layer coating thickness was 35μ-,
A polyimide pattern having sufficient adhesion to the substrate was obtained by the same method as in Example 4 except that the exposure time was 3 minutes.

Example 7 100 g of P-3 as a polymer, 881 tetraethylene glycol diacrylate as a monomer, 5 g of 1-phenyl-propanedione-2-(0-ethoxycarbonyl)oxime as an initiator, 3 g of Michler's ketone, and a sensitizer. 1.5g of jetanol aniline,
2-mercaptobenzothiazole was used as a mercaptan compound, and jetoxy-3-glycidoxypropylmethylsilane was used as a functional dialkoxysilane compound.
g, N-nitrosodiphenylamine 0 as a polymerization inhibitor
．． 2 g was dissolved in a mixed solvent of 100 g of cyclopentanone and 50 g of N-methylpyrrolidone to obtain solution C.-3. Solution C-3 was coated with a thickness of 6 μm using a spin code method.
It was laminated to a thickness of 10 .mu.m on a silicon wafer having an aluminum wiring layer having a width of 20 .mu.m. Next, a 40 μm thick dry film obtained by coating solution C-34 on a 125 μm thick PET film was coated at 130° C. using a hot roll laminator at 2 Kg/C. l
It was laminated on this silicone wafer under conditions I. The PET film on the laminated film was peeled off, and exposed for 3 minutes under a nitrogen atmosphere through a mask film using an ultra-high pressure mercury lamp (8 mW/cj). When this was developed with a developer of N-methylpyrrolidone/xylene (1:1 volume) and rinsed with isopropyl alcohol, a sharp pattern was obtained. It was heat-treated for 2 hours at 400° C. for 1 hour to be imidized, and a polyimide pattern having sufficient adhesion even in the stepped portions of the wiring layer was obtained.

Claims (1)

[Claims] (1) (a) The thermogravimetric decrease starting temperature is 31% due to heat treatment.
A photosensitive aromatic precursor that can be converted into a heat-resistant aromatic polymer having a temperature of 0°C or higher, or a soluble photosensitive aromatic polymer having a thermal weight loss initiation temperature of 310°C or higher, and (b) a photopolymerization initiator. A photoresist film containing as an essential component is laminated on a base material, the photoresist layer is irradiated with actinic rays through a photomask, and after development, it is made highly insulating by heat treatment. A method for forming an image having heat resistance, characterized by: